Home Products ECO Hybrid Heat Pump System

Share this page

Integrating an air-to-water heat pump within a boiler hydronic heating system

ECO^® Hybrid Dual Fuel Hydronic System

The New ECO Hybrid is a dual-fuel hydronic system that integrates our ECO HP air-to-water heat pump with a high-efficiency boiler, providing optimal heating performance. It automatically switches between the heat pump and boiler based on outdoor temperatures to maximize energy efficiency and comfort. Ideal for retrofits and new installations, the ECO HP helps homeowners reduce their carbon footprint and may reduce energy costs while maintaining reliable heat.

Upgrade to an ECO Hybrid System and Save Big

Save more when you choose an ECO Hybrid Dual Fuel Hydronic System. For a limited time, homeowners can receive $1,000 in rebates on qualifying ECO HP Air-to-Water Heat Pump Systems, while participating contractors earn a $200 incentive for every eligible installation. It’s a smart time to upgrade to efficient, year-round comfort.

Learn HOW YOU CAN SAVE!

Features

Highly Efficient

Achieves efficiencies up to 5.37 COP for optimal savings

Eco-friendly Refrigerant

Heat pump uses R32 refrigerant for improved sustainability

Flexible Applications

Use for radiant heating and domestic hot water

Installation Ready

Easy-Up manifold included and accessory kit available

Optimal Design

Low decibel, quiet operation plus compact design

Cost Savings

Minimal maintenance, rebates and tax credits available in some areas

Locate a contractor Locate a Distributor Product Comparison Tool

See it in action

FAQ

An air-to-water heat pump transfers heat from outdoor air into water that is circulated throughout your home’s heating system. Unlike traditional forced-air heat pumps and mini splits that heat air directly, air-to-water systems work with hydronic applications such as radiant floor heating, baseboards, fan coils, and domestic hot water systems. Because they transfer heat rather than generate it through combustion, they can operate very efficiently under the right conditions. Air-to-water heat pumps are becoming increasingly popular among homeowners looking to reduce energy consumption while maintaining the comfort of hydronic heating. They can also be integrated with existing boilers as part of a dual fuel heating system.

An air-to-water heat pump uses a refrigeration cycle to capture thermal energy from outdoor air and transfer it into water. That heated water is then distributed throughout the home to provide space heating and, in some systems, domestic hot water. Even during colder weather, outdoor air contains usable heat that the system can extract. Because the system moves heat rather than creates it, it can deliver more heat energy than the electricity it consumes. When paired with a boiler, the system can automatically optimize performance based on outdoor conditions and heating demand.

In a hybrid system, the air-to-water heat pump and boiler work together to provide efficient, reliable comfort throughout the year. The heat pump serves as the primary heating source for most of the season, efficiently handling the majority of the home’s heating load. As outdoor temperatures drop, the system automatically transitions to the boiler when it becomes the more effective heating source. This approach helps maximize energy savings while ensuring homeowners have dependable heat during extreme winter conditions. By allowing each system to operate when it performs best, a hybrid design can improve efficiency, comfort, and overall system longevity.

A hybrid heating system combines two heating technologies that work together to optimize comfort, efficiency, and operating costs. In the case of Weil-McLain ECO Hybrid, an air-to-water heat pump is paired with a fossil-fuel fired boiler to create a flexible heating solution. The system automatically determines which heat source is best suited for current weather conditions and heating demand. This allows homeowners to take advantage of the efficiency of a heat pump while maintaining the performance and reliability of a boiler when temperatures become extremely cold. Hybrid systems can be particularly beneficial in northern climates where heating demands vary significantly throughout the year.

Modern air-to-water heat pumps can operate effectively in cold climates, but performance varies based on outdoor temperatures and system design. As temperatures drop, heat pumps must work harder to extract heat from the air, which can reduce efficiency. That’s why many homeowners in colder regions choose a hybrid approach that incorporates a boiler for supplemental heating during the coldest periods. This combination allows the heat pump to handle much of the heating season while the boiler provides additional capacity when needed. The result is a system designed to deliver both efficiency and comfort throughout winter.

An ECO Hybrid system may be a good fit for homeowners who want to reduce fuel consumption without sacrificing comfort or reliability. It can be particularly attractive for homes that already use hydronic heating systems such as radiant floors, baseboards, or boilers. Homeowners in colder climates who are interested in heat pump technology but have concerns about winter performance may also benefit from a hybrid approach. Those with oil, propane, or older heating systems often see opportunities to improve efficiency while maintaining dependable heat. A qualified contractor can evaluate whether a hybrid system aligns with your home’s heating needs and existing infrastructure.

Yes. Depending on the system configuration, ECO Hybrid can be designed to support both space heating and domestic hot water production. Combining these functions into a single integrated system can improve overall efficiency and reduce the need for separate equipment. Domestic hot water capabilities will vary based on system design, household demand, and installation requirements. Homeowners should work with their contractor to determine the best configuration for their needs. An integrated approach can help maximize the value of the system while simplifying home comfort management.

Energy savings depend on factors such as climate, fuel costs, home insulation, and the existing heating system. In many applications, an air-to-water heat pump can handle a significant portion of annual heating demand more efficiently than traditional heating equipment. By allowing the heat pump to operate during favorable conditions and the boiler to operate during colder periods, a hybrid system can help reduce overall energy consumption. Some homeowners may see substantial reductions in fuel use, particularly when upgrading from older or less efficient equipment. Your local Weil-McLain contractor can provide a more accurate estimate based on your home’s specific conditions.

Many heat pump and high-efficiency heating projects may qualify for federal, state, local, or utility-sponsored incentive programs. Eligibility and incentive amounts vary based on location, equipment specifications, and program requirements. These incentives can help offset upfront installation costs and improve the overall return on investment. Because programs change frequently, homeowners should verify current opportunities before making a purchase decision. A Weil-McLain contractor can often help identify available rebates and incentives in your area.

In many cases, yes. One of the advantages of a hybrid heating approach is that an air-to-water heat pump can often be integrated with an existing boiler rather than requiring a complete system replacement. This allows homeowners to improve efficiency and reduce fuel consumption while continuing to utilize equipment that still has useful service life remaining. Retrofitting a heat pump alongside an existing boiler can also reduce upfront costs compared to a full heating system replacement. A contractor can evaluate your current equipment and determine whether it is compatible with a hybrid upgrade.

The lifespan of an air-to-water heat pump depends on factors such as climate, usage patterns, installation quality, and maintenance. Many systems can provide reliable performance for 10 to 20 years when properly maintained. Routine inspections and preventative maintenance can help identify small issues before they become larger problems. Because hybrid systems share heating demand between multiple components, they may reduce wear on individual pieces of equipment. Choosing quality equipment and working with experienced installers can help maximize long-term performance.

Regular maintenance helps ensure efficient operation and reliable performance. Homeowners should keep outdoor units free from leaves, debris, and obstructions that could restrict airflow. Periodic inspections by a qualified technician can help identify issues with refrigerant levels, pumps, controls, and other system components. Hydronic systems may also require maintenance related to water circulation and system pressure. Following manufacturer recommendations and scheduling routine service can help extend equipment life and maintain peak efficiency.

Technical Specs

Model	Nominal Capacity* (MBH)	COP @ Nominal	Input @ Nominal (kW)	Max Capacity (MBH)	Max Input (kW)	Min Capacity (MBH)	Min Input (kW)	Outdoor Temp (Deg °F)	Heating Supply Temp (Deg °F)
ECOHP-41	41.2	4.95	2.44	51.1	3.19	21.1	1.21	-13 – 109	77 – 149
ECOHP-48	49.5	4.7	3.09	56.0	3.66	21.1	1.21	-13 – 109	77 – 149
ECOHP-55	54.6	4.5	3.56	59.3	3.93	21.1	1.21	-13 – 109	77 – 149

*44.6° F outdoor temperature, 95° F water outlet temperature

Flow

3.1 – 13.2 GPM

Pressure Drop @ 12.1 GPM

9 FT

Piping Connections

1 Inch

Type

R-32

Factory Charge

4.04 LBS

Max Pre-Charged Pipe Length

49.2 FT

Additional Charge

0.41 OZ/FT

Liquid Line Connection

3/8 IN

Gas Line Connection

5/8 In

Compressor Type

Twin Rotary

ODU Power

208–230/1/6 V/Ph/Hz

Compressor RLA

26 A

ODU Fan FLA

1.3 A

ODU MCA

34 A

ODU MOP

50 A

IDU Power

110-120/1/60 V/Ph/Hz

IDU MCA

1.5 A

IDU MOP

15 A

IDU Net

69 LBS

IDU Shipping

78 LBS

ODU Net

212 LBS

ODU Shipping

255 LBS

Downloads

Product Manuals

ECO HP IDU Manual ECO HP ODU Manual

Sales Collateral

ECO HP Case Study: Hybrid Hydronic Heat + DHW for Residential Homes ECO HP Brochure

In the news

Boiler Maintenance | Featured Article
What Is an Air-to-Water Heat Pump? How It Works & Common Applications
Heat pumps have become one of the fastest-growing home heating technologies as more homeowners seek to improve energy efficiency, reduce fuel consumption, and lower carbon emissions. They offer an energy-efficient…
News | Featured Article
Save Up to $1,200 with the ECO Hybrid Smarter Heating Rebate
Homeowners looking to upgrade to a more energy-efficient heating system now have even more reason to make the switch. The Weil-McLain ECO® Hybrid Smarter Heating Rebate offers up to $1,000…
News | Featured Article
ECO™ Hybrid System Named #1 Product of the Year by Plumbing & Mechanical
The ECO™ Hybrid System from Weil‑McLain has been recognized as the #1 Product of the Year for 2025 by Plumbing & Mechanical magazine. This top ranking reflects strong industry interest…
Featured Article
Hybrid Hydronic Heat + DHW for Residential Homes
Hybrid system combines electric heat pump with high-efficiency boiler for radiant heating, snow melt, and hot water—maximizing efficiency while ensuring reliability in extreme cold.
News Article
Heat Pump Combines Efficiency with Reliability
Retrofit Magazine profiles the ECO HP, focusing on how the system blends high energy efficiency with proven reliability for renovation and retrofit projects.
News Article
Weil-McLain introduces ECO HP Air-to-Water Heat Pump for hybrid hydronic heating
Indoor Comfort Marketing covers the launch of the ECO HP, emphasizing its role in offering contractors and homeowners a reliable, energy-smart heating option.
News Article
ECO HP AIR-TO-WATER ELECTRIC HEAT PUMP
An overview of the ECO HP’s electric heat pump capabilities, promoting its advantages in decarbonizing and modernizing home heating systems.
News Article
Weil-McLain: ECO HP Air-to-Water Heat Pump
FacilitiesNet highlights the key features of the ECO HP, noting its ability to improve energy efficiency and heating reliability where it’s needed.
News Article
Weil-McLain introduces ECO HP Air-to-Water Heat Pump for hybrid dual-fuel hydronic heating
Announcement of the ECO HP system, underlining its high-efficiency performance and flexible integration into existing boiler-based hydronic systems.
News Article
Weil-McLain launches dual-fuel heat pumps for residential, light commercial applications
A news story detailing Weil-McLain’s ECO HP launch, focusing on its dual-fuel capabilities and the system’s relevance for renewable energy markets.
News Article
Weil-McLain Introduces Air-to-Water Heat Pump for Hybrid Dual-Fuel Hydronic Heating
Coverage of the new ECO HP air-to-water heat pump introduction, emphasizing Weil-McLain’s commitment to efficient, modern heating technologies.
News Article
Weil-McLain air-to-water heat pump
A news announcement highlighting the launch of Weil-McLain’s ECO HP, designed to meet the growing demand for sustainable hydronic heating solutions.
Featured Article
Overview Video: Weil-McLain ECO Hybrid Dual Fuel Hydronic System Overview
An article featuring Weil-McLain’s new ECO Hybrid overview video, showcasing the system’s innovative dual-fuel design and energy-saving benefits.
News Article
Weil-McLain ECO HP Air-to-Water Heat Pump
An announcement covering the key features of the new ECO HP, including high-efficiency operation, dual-fuel capabilities, and easy integration with existing boiler systems.
News Article
Weil-McLain® Introduces ECO™ HP Air-to-Water Heat Pump for Hybrid Dual-Fuel Hydronic Heating
A news post announcing the launch of the ECO HP air-to-water heat pump, detailing its application for sustainable hydronic heating in homes and small businesses.